Method of treating silk-containing wool materials



Nov- 12, 1929- D. c. CHISHOLM ET AL METHOD OF TREATING SILK CONTAINING WOOL MATERIALS ACID Filed May 12, 1926 A L A L:

1 NVEN TOR 5 M 5 Z I M WM 0 T fin vA a 7 6 1 0 m flm w lpw 1M Patented Nov. 12, 1929 UNITED STATES PATENT OFFICE DOUGLAS C. CHISHOLM AND JOHN A. HANNUM, OF CLEVELAND, OHIO, ASSIGNOBS TO i GEORGE E. COLLINGS, TRUSTEE, OF CLEVELAND, OHIO METHOD OF TREATING SILK-CONTAINING WOOL MATERIALS Application filed. May 12,

This invention relates, to the utilization of wool mixed scrap or waste material, and particularly mixed wool and silk. It has heretofore been known that if scrap containing wool and cotton be treated with sulphuric acid, or.with hydrochloric acid gas, the cotton fibers are destroyed and the wool is left available to be worked up for re-use. It has also been known that if mixed wool and artificial silk he, treated with hydrochloric acid, the artilicial silk is destroyed and-the wool is not. The artificial silk is a form of cellulose and chemically is allied in general with cotton. Where wool is mixed with natural silk however. it has heretofore been considered as impossible to eliminate such silk without also harming the wool. in fact the wool and silk are chemically both of protein character and it has heretofore been thought impossible to act upon one without likewise affecting the other. .In our work on this problem, we have now found however, that silk can be destroyed and the wool be left for re-use, and our procedure makes possible the working up of waste wool and silk which was heretofore a loss so far as the recovery of the wool was concerned.

To the accomplishment of the foregoing and related ends, the invention, then consists of the procedure and means hereinafter fully described, and particularly pointed out in the claims, the annexed drawing and the following description setting forth in detail certain features embodying the invention,, such disclosed features constituting however, but one of various ways in which the principle of the invention may be used.

In said annexed drawing Fig. 1 is a semi-diagrammatic vertical sec tional view taken longitudinally through an apparatus suitable for carrying out the-invention; and Fig. 2 is a section taken on the. plane indicated by line II-II, Fig. 1.

In proceeding in accordance with our invention, material containing wool and natural silk is treated with an agent which exercises a differential disintegrating action, the silk being the portion attacked. The material subjected to the action of hydrogen chloride in solution, for instance most usually 1926. Serial No. 103,505.

a solution in water, a solution of about 30 per cent ordinarily being suitable. While submersion in a vat of hydrochloric acid may in some cases be desirable, we generally prefer to feed the wool and silk material or scrap to a conveyor, as endless conveyor 1, while acid from a tank 2 is sprayed thereon. The conveyor is of rubber or other suitable acid-proof material, supported by rolls 3, 4:, one or both being driven from a suitable source of power, and intermediate rollers 5 may be utilized for additional support if desired. A convenient feed arrangmnent is a hopper 6 having a con veyor 7 for supplying material to the belt. It is desirable to enclose the conveyor 1 with a housing 8 and at the lower part of the housing, drains 9, 10 and 11 may be provided, these being respectively arranged under the areas supplied by the tanks 2, 12 and the water inlet 13. Spray heads may be employed for these respective sources of liquid, but preferably one or more perforated pipes O is provided inthe upper portion of the housing, these being perforated in a manner to allow the fluid fed from the tanks or water line to spray or sprinkle down over the material as carried along by the endless conveyor. Advantageously partitions 14L and 15 may be arranged to divide the casing up into compartments A, N and TV, and in this manner the respective zones of treatment may be kept separated and as further provision, a pair of squeeze rolls 16, 17 is desirably placed atthe discharge end of each compartment.

The material to be treated is put into the hopper (S from which it is fed out to the endless conveyor 1, and hydrochloric acid is sprayed upon it from the tank 2, the valves therefrom being suitably regulated to allow an adequate supply of the acid to the sprayer and excess acid is drained off by the drain 9 and may be returned by the pum 18 through a pipe 19 to the tank 2. After passing through thefirst set of squeeze rolls 16, 17, the material is now again sprayed with a neutralizing solution from the tank 12. This solution is an alkali and conveniently may be a solution of sodium hydroxide of suitable strength for convenient neutralization, for instance about 5 per cent. Surplus solution 

